Power impact tools (e.g., pneumatic, hydraulic, electric, etc.) are well known in the art. Power impact tools produce forces on a workpiece by the repeated impact of a motor-driven hammer on an anvil that is mechanically connected, directly or indirectly, to exert a force on the workpiece. Some power impact tools exert linear forces. Other power impact tools exert torque, which is a twisting force.
One difficulty in current power impact tools is that power may be applied too long to the workpiece. The accumulation of impacts on any already tightened workpiece may cause damage. Current power impact tools shut off when the operator manually enables shutting off. For example, in a pneumatic hand tool such as a torque wrench, the operator releases the trigger valve to shut off the supply of compressed air to the tool motor. The number of impact forces delivered to the workpiece depends on the reflexes and attentiveness of the tool operator. During any delay, the workpiece may become overtorqued and damaged.
Applicant's co-pending application Ser. No. 10/213,702, discloses, among other things, a modular control apparatus. One modular control apparatus, a torque-timing device, is operative to limit the amount of time that torque will be applied after the operator initiates torque production from a power impact tool. For example, the operator may squeeze the trigger of a power impact torque wrench to initiate torque production. The modular torque-timing device is configured to be used with a particular family of power impact tools. It is desired to enable operators to use the modular torque-timing device with tools that were not originally manufactured to interface with a modular torque-timing device. Similarly, it is desirable to enable operators to use other modular control apparatuses with tools that were not originally manufactured to interface with a modular control apparatus.
Accordingly, there is a need in the field of power impact tools for an after-market product to provide more control of forces ultimately applied to a workpiece by a power impact tool.